Autonomic nervous system Flashcards
preganglionic
-all preganglionic receptors are nicotinic/Ach
postganglionic: parasympathetic
- 1) nicotinic=somatic NS
2) muscarinic =smooth msucle, cardiac, muscle, exocrine glands - Ach for both types (cholinergic postganglionic fibers)
postganglionic: sympathetic
- alpha and beta receptors
- NE
- adrenergic fibers
parasympathetic preganglionic
- craniosacral
- synapse near site of smooth muscle, cardiac muscle, exocrine glands–long
parasympathetic postganglionic
-are short, b/c come from ganglia close to organs being innervated
sympathetic preganglionic
thoracolumbar
sympathetic postganglionic
- long
- b-1/b2/a-1 are adrenergic receptors
-a-2:
- presynaptic and inhibitory
- when bound to NE, inhibit Adenylate cyclase, and inhibit cAMP formation, dec Ca entry to neuron terminal, decreasing release of NE into synaptic cleft
NE action termination
- reuptake into postganglionic nerve
- MAO is in cytoplasm to deactivate it
Ach action termination
acetylcholinesterase hydrolizes it
somatic NS
-cholinergic efferent fibers from central cell bodies exit spinal cord and synapse to nicotinic receptors on skeletal muscle
adrenal
-Acetylcholine cause release of epinephine